{"release":{"id":"DR1","released_on":"2026-08-21","doi":null,"url":"https://spacecatalog.org/releases#dr1"},"epoch":{"requested":"now","label":"J2026.679","julian_year":2026.679,"time":"2026-09-06T03:39:19.361Z","years_from_j2000":26.679,"frame":"date","applied":"Proper motion, then precession and nutation. The catalogued J2000 position is carried along the great circle the object's own published motion puts it on, at a constant velocity, and the result is referred to the true equator and equinox of this instant. Those are separate things: the motion moves the object, and the rotation turns the grid under it by about fifty arcseconds a year, with nutation adding up to another seventeen.","excluded":"Parallax, the radial-velocity perspective term, aberration and refraction; each is below the accuracy of the catalogued positions themselves. An object with no published proper motion comes back where the catalogue has it rather than at a fabricated zero, and says so with a null pm_ra_mas_yr. A body with no fixed position is not propagated at all — its place comes from an ephemeris, which is what /api/v1/visible answers with."},"slug":"hd-16141-b","name":"HD 16141 b","class":"gas_giant","category":"exoplanet","object_type":"Gas giant","mag":null,"mag_band":null,"abs_mag":null,"abs_mag_band":null,"distance_ly":123.24177504042638,"distance_method":"NASA Exoplanet Archive sy_dist (TICv8, 2019AJ....158..138S)","ra_deg":38.8323674,"dec_deg":-3.5624887,"epoch_ra_deg":39.170902,"epoch_dec_deg":-3.444828,"epoch_moved_arcsec":null,"pm_ra_mas_yr":null,"pm_dec_mas_yr":null,"orbits":"HD 16141","semi_major_axis_km":53855233.45199999,"periapsis_km":null,"mass_kg":4.9351486948923485e+26,"mass_msun":0.000248196,"constellation":"Cetus","discovered":"2000","featured":false,"url":"https://spacecatalog.org/object/hd-16141-b","radius_km":69521.29000000001,"radius_kind":null,"data_quality":null,"description":null,"properties":{"host_star":"HD 16141","host_v_mag":6.834,"eccentricity":0.25,"uncertainties":{"mass_kg":[3.796268226840268e+25,3.796268226840268e+25],"distance_ly":[0.2713621062603305,0.2726667317711975],"eccentricity":[0.05,0.05],"host_mass_solar":[0.06,0.06],"host_radius_solar":[0.02,0.02],"host_temperature_k":[9,9],"semi_major_axis_km":[1495978.707,1495978.707],"orbital_period_days":[0.055,0.055],"argument_of_periastron_deg":[14,14]},"host_mass_solar":1.11,"stars_in_system":2,"discovery_method":"Radial Velocity","host_radius_solar":1.48,"planets_in_system":1,"discovery_facility":"W. M. Keck Observatory","host_spectral_type":"G5 IV","host_temperature_k":5757,"orbital_period_days":75.523,"periastron_epoch_bjd":2450338.1,"transit_midpoint_bjd":2451932.3,"equilibrium_temperature_k":562.87,"argument_of_periastron_deg":42},"designations":[{"catalog":"Exoplanet","designation":"HD 16141 b"},{"catalog":"Host star","designation":"HD 16141"}],"source":{"id":"exoplanet_archive","name":"NASA Exoplanet Archive (Planetary Systems Composite Parameters)","url":"https://exoplanetarchive.ipac.caltech.edu/cgi-bin/TblView/nph-tblView?app=ExoTbls&config=PSCompPars","license":"Public domain (NASA)"},"updated_at":"2026-09-02T19:50:56.720Z","attribution":"Data from SpaceCatalog.org. Individual records carry their source and license in `source`; attribution is required for CC-BY and CC-BY-SA rows."}